This invention relates generally to electric machines and, more particularly, to an optimization strategy for designing induction motors and generators.
Known motors including synchronous machines, non-synchronous machines, and direct current (DC) machines, include a motor housing, a stator including one or more windings, or one or more permanent magnets, and a rotor assembly. The rotor assembly includes a rotor core and a rotor shaft that extends through the rotor core. The rotor is constructed of a plurality of laminations and includes one or more armature windings one or more permanent magnets. The motor housing includes at least one endshield and houses at least a portion of the rotor assembly. At least one bearing receives and the rotor shaft, and is positioned between the endshield and an inner bearing cap to enable the rotor shaft to rotate during operation.
At least some known motors are configured to satisfy pre-determined steady state operating requirements such as a rated voltage, a locked rotor voltage, and a breakdown voltage. Two key components for satisfying operating requirements are lamination geometry and winding variables. The lamination geometry and winding variables are configured to facilitate optimizing performance cost variables associated with the motor design. At least some known design methods attempt to optimize a winding after a lamination design is know. This design method may only provide acceptable results the bounds of the particular lamination, and as such, does not allow the assertion that a global optimum has been found. Other known methods attempt to simultaneously optimize all the winding variables and lamination geometry variables. This design is much more complex and computationally expensive.